According to forecasts recently published by Cisco Visual Networking Index, global IP traffic has increased more than fourfold in the past few years, and will continue to increase over the coming years. Overall, IP traffic will grow at a compound annual growth rate of about 25 percent from 2012 to 2017. Busy hour Internet traffic is growing more rapidly than average Internet traffic. Busy hour Internet traffic will in 2017 reach the equivalent of 720 million people streaming a high-definition video continuously. It is needless to say that the demands on communication infrastructure will be increasing during a foreseeable time period.
The number of devices connected to IP networks will be nearly three times as high as the global population in 2017. Also the IP traffic per capita will be increased by about three times in 2017 compared with 2012 and more particularly, the IP traffic is expected to reach to 16 gigabytes per capita in 2017 compared with 6 gigabytes per capita in 2012. The IP traffic will be accelerated in part by the increase in the number of devices and by continually introduced new and advanced functionality. This new functionality will often require substantial amounts of data to be transferred.
It is clear from the above that all applicable quantitative numbers related to the mobile broadband traffic globally are growing significantly every year. No real evidence that indicate a slowdown of this trend is yet to be seen in the market. However, it is conceivable that lack of sufficient server resources may in future reduce or at least during certain periods in time limit the speed of further growth and development. Server capacity for managing the growing demands for distributing the increasing amounts of information to be distributed over the Internet is therefore on its way to becoming a bottleneck.
A problem related to management of rapidly growing volumes of data traffic, is the management of increasing end user bandwidth with the introduction new technologies, such as HSPA+ (Evolved High-Speed Packet Access) and LTE (Long Term Evolution) technologies.
When opening a complex web page containing multiple resources, such as high resolution images, from the same web server domain name, web browsers are allowed to open a small and limited number of TCP/IP connections towards that server. This number has a maximum of typically four or six connections depending on the type and version of browser used. All of the resources from that domain are to be downloaded using this pool of opened TCP/IP connections. Often in a large and complex web page there can be 70 or more images, so the process of downloading all of the images requires ten or more request response pairs, each one utilizing an additional round trip to the server for each so-called HTTP (Hypertext Transfer Protocol) GET request. A consequence of that traffic is that the downloading process is perceived as disturbingly slow, especially by an experienced and/or professional user. The time delay in a web browser as experienced by a user, i.e. the latency of the computer system, is therefore an important parameter to improve. A part of the latency is also dependent on the physical distance to the content source.
Modern fixed as well as mobile networks usually have more than enough bandwidth to download many more resources in parallel than is possible, due to the mentioned constraints related to rules of the particular communication protocol used. This is true also when considering that resources requests can be serialized. Therefore, congestion problems in networks that are associated with downloading of web content, problems that used to be mainly related to restrictions in available bandwidth, are no longer the main concern. The real problem has moved from being related to the actual transfer of data to instead being mainly related to latency effects in the system.
Numerous approaches have been tried over the years to minimise the effects of latency. One of the approaches is to accelerate load times of web page content in that the website provider distributes resources that constitute the web page across multiple web servers on different domains. This causes the browser to open more simultaneous connections than normally allowed. Resources that would normally be downloaded on a single domain are allowed to be split and can then simultaneously be downloaded across multiple domains. This is called domain sharding. This approach potentially allows many more resources to be downloaded in parallel, and reduces the overall load time of the content of a web page. Similar domain sharding methods of accelerating downloading of web page content are widely used, and enable web browsers to make better use of high-bandwidth internet connections in computer systems of today.
A prior art method related to domain sharding is published in U.S. Pat. No. 7,398,314, which discloses a technique for downloading multiple objects from at least one server in an accelerated manner. A so-called spoofer is utilized to intercept traffic between a server and a client, which traffic is modified so that it appears as though objects from a single server are actually being sourced from multiple servers. This allows for parallel download of objects and thus also allows for a reduction of the amount of time necessary to download the objects, as the relative negotiation time is reduced.
From a more technical perspective, previous approaches are based on rewriting a portion of the host name in the HTML (Hypertext Markup Language) to a local IP address on the proxy node system. This rewriting process is then either served from a cache memory or retrieved from an originally used resource in an alternative manner. As an alternative to the processes described, a domain name server (DNS) could be used so as to make additional sub domains appear.
However, all the mentioned previous attempts and approaches to use domain sharding suffer from a number of limitations. One of the limitations is that the browser uses domain name restrictions in cookies to place restrictions on content that originate from a domain that is not listed in the cookie. To mention only one of several disadvantages of such a method, it could adversely affect for example recognition of individual subscribers in subscription services. Such subscription services oftentimes rely on host name-based mechanisms for restricting content, and a problem of recognition occurs when the modified host name does not any longer match information contained in a corresponding cookie.